[en] The Institute for Neutron Physics and Reactor Technology treats research problems of nuclear engineering mainly those that are related to the development of sodium-cooled fast breeder reactors and fusion reactor technology. The activities are in approximately equal parts of an experimental and theoretical nature. A great part of the research activities is performed in co-operation with other institutes and industrial groups in the framework of projects. For the Fast Breeder Reactor Project the Institute works on reactor physical design and safety problems by the core of large-scale fast breeder reactors. Questions concerning the consequences of accidents in lightwater reactors upon the environment and the population are treated as part of the Nuclear Safety project. The Institute contributes to the Reprocessing Project with theoretical investigations on the physics of the fuel cycle and by developing control devices for a reprocessing plant. In the framework of the Fusion Projekt the Institute is concerned with neutron physical and technological questions of the the breeder blanket. Independent institutional work concerns technical and physical questions on the interaction between light ion beams of a high energy density and substances. Apart from this, investigations are carried out on the application of nuclear energy in the field of traffic with hydrogen as energy carrier. (RW)